子宫肌瘤是单克隆肿瘤，通常存在遗传异常，并且与全基因组无细胞 DNA (cfDNA) 筛查结果假阳性相关，特别是当子宫肌瘤较大时。肌瘤也可能通过影响胎儿分数或由于其遗传异常混淆 cfDNA 算法而增加 cfDNA 失败的风险。我们的目的是调查子宫肌瘤和 cfDNA 非信息性结果之间可能存在的关联。这是一项回顾性队列研究，对象是 2013 年至 2020 年间接受胎儿染色体异常 cfDNA 筛查的女性，比较了 24 日前任何产科超声记录有子宫肌瘤的怀孕情况和没有子宫肌瘤的情况。怀孕几周。使用单变量和多变量逻辑回归模型来研究肌瘤与 cfDNA 失败之间的关联，调整胎龄、产妇年龄、采血时的体重和身高、受孕方式、多胎妊娠和测试平台（染色体选择性或全基因组） ）。根据肌瘤数量和肌瘤总体积对分析进行分层。使用线性回归评估肌瘤对胎儿分数的影响，调整相同的协变量。在 19 818 例接受 cfDNA 筛查的妊娠中，2038 例 (10.28%) 报告了肌瘤，228 例 (1.15%) 首次筛查尝试时 cfDNA 失败）怀孕。 1.96% 的子宫肌瘤妊娠和 1.06% 的无子宫肌瘤妊娠出现非信息性结果（调整后的比值比 (aOR)，2.40 (95%CI，1.65-3.48)）。第一次筛查失败的风险随着肌瘤数量（有四个或更多肌瘤的女性，aOR为5.05（95%CI，2.29-11.13））和肌瘤总体积的增加而逐渐增加，超过5倍和肌瘤体积为 100.1-400mL（aOR，5.52（95%CI，2.30-13.25））和 > 400mL（aOR，14.80（95%CI，4.50-48.69））的女性风险分别增加 14 倍。尽管染色体选择性筛查的测试失败比全基因组筛查更常见，但子宫肌瘤同样增加了两种筛查平台失败的风险。与无子宫肌瘤的妊娠相比，有子宫肌瘤的孕妇的胎儿分数平均降低 0.61%（调整后的平均差为 -0.61%（95% CI，-0.77% 至 -0.45%））。子宫肌瘤与较低的胎儿分数相关，并且cfDNA 筛查失败的风险增加。这种关联的强度随着肌瘤数量和体积的增加而增加。 © 2024 作者。产科超声

Uterine fibroids are monoclonal tumors, which are often genetically abnormal and associated with false-positive genome-wide cell-free DNA (cfDNA) screening results, particularly when large. It is plausible that fibroids may also increase the risk of cfDNA failure by affecting fetal fraction or due to their genetic anomalies confounding cfDNA algorithms. We aimed to investigate a possible association between fibroids and cfDNA non-informative results.This was a retrospective cohort study of women undergoing cfDNA screening for fetal chromosomal abnormalities between 2013 and 2020, comparing pregnancies with vs without uterine fibroids recorded on any obstetric ultrasound before 24 weeks' gestation. Univariable and multivariable logistic regression models were used to investigate the association between fibroids and cfDNA failure, adjusting for gestational age, maternal age, weight and height at blood sampling, mode of conception, multiple gestation and test platform (chromosome-selective or genome-wide). Analyses were stratified according to the number of fibroids and total fibroid volume. The impact of fibroids on fetal fraction was assessed using linear regression, adjusting for the same covariates.Among 19 818 pregnancies undergoing cfDNA screening, fibroids were reported in 2038 (10.28%) and cfDNA failure at the first screening attempt occurred in 228 (1.15%) pregnancies. Non-informative results occurred in 1.96% of pregnancies with fibroids and 1.06% of pregnancies without fibroids (adjusted odds ratio (aOR), 2.40 (95% CI, 1.65-3.48)). The risk of failure in the first screening attempt increased progressively with the number of fibroids (aOR, 5.05 (95% CI, 2.29-11.13) in women with four or more fibroids) and total fibroid volume, with greater than a 5-fold and 14-fold increase in risk among women with fibroid volumes of 100.1-400 mL (aOR, 5.52 (95% CI, 2.30-13.25)) and > 400 mL (aOR, 14.80 (95% CI, 4.50-48.69)), respectively. Although test failure was more common with chromosome-selective than genome-wide screening, fibroids similarly increased the risk of failure of both screening platforms. Compared to pregnancies without fibroids, those with fibroids had a fetal fraction on average 0.61% lower (adjusted mean difference, -0.61% (95% CI, -0.77% to -0.45%)).Uterine fibroids are associated with lower fetal fraction and an increased risk of cfDNA screening failure. The strength of this association increases with increasing fibroid number and volume. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.© 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.